Optimal Timing to Assess Drain Amylase Concentration after Elective Gastrectomy

Prophylactic Drain Placement and Postoperative Invasive Procedures After Gastrectomy: The Abdominal Drain After Gastrectomy (ADIGE) Randomized Clinical Trial

Importance

Evidence suggests that prophylactic abdominal drainage after gastrectomy for cancer may reduce postoperative morbidity and hospital stay but this evidence comes from small studies with a high risk of bias. Further research is needed to determine whether drains safely meet their primary purpose of identifying and managing postoperative intraperitoneal collections without the need for reoperation or additional percutaneous drainage.

Objective

To determine whether avoiding routine abdominal drainage increased postoperative invasive procedures.

Design, Setting, and Participants

The Abdominal Drain in Gastrectomy (ADIGE) Trial was a multicenter prospective randomized noninferiority trial. Enrollment spanned from December 2019 to January 2023. Follow-up evaluations were completed at 30 and 90 days. Eleven centers within the Italian Research Group for Gastric Cancer, encompassing both academic medical centers and community hospitals, were included. Patients with gastric cancer undergoing subtotal or total gastrectomy with curative intent were eligible, excluding those younger than 18 years, with serious comorbidities, or undergoing procedure types outside the scope of the study. Of 803 patients assessed for eligibility, 404 were randomized and 390 were included in final analyses.

Interventions

Patients were randomized 1:1 into prophylactic drain or no drain arms.

Main Outcomes and Measures

The primary end point was a modified intention-to-treat (mITT) analysis measuring reoperation or percutaneous drainage within 30 postoperative days. The null hypothesis was rejected when the 90% CI upper limit of the proportion difference did not exceed 3.56%. The calculated sample size to achieve 80% power with a 10% dropout rate was 404 patients (202 in each group). Surgeons and patients were blinded until gastrointestinal reconstruction.

Results

Of the 404 patients randomized 226 (57.8%) were male; the median (IQR) age was 71 (62-78) years. Intraoperative identification of nonresectable disease occurred in 14 patients, leading to their exclusion from the study, leaving 390 patients. In the mITT analysis, 15 patients (7.7%) in the drain group needed reoperation or percutaneous drainage by postoperative day 30 vs 29 (15%) in the no drain group, favoring the drain group (difference, 7.2%; 90% CI, 2.1-12.4; P = .02). Of note, the difference in the primary composite end point was entirely due to a similar difference in reoperation (5.1% in the drain group vs 12.4% in the no drain group; P = .01). Drain-related complications occurred in 4 patients.

Conclusions and Relevance

The findings of this study indicate that refraining from prophylactic drain use after gastrectomy heightened the risk of postoperative invasive procedures, discouraging its avoidance. Future studies identifying high-risk groups could optimize prophylactic drainage decisions.

Trial Registration

ClinicalTrials.gov Identifier: NCT04227951.

The Amount and Concentration of Drain Amylase Together Predict Postoperative Pancreatic Fistula after Gastric Cancer Surgery More Accurately than the Concentration Alone

Introduction The drain amylase concentration (dAmy-C) is a useful marker for predicting pancreatic fistula after gastric cancer surgery. However, dAmy-C might be reduced in cases of high drainage volume. Therefore, we hypothesized that we could accurately assess the amount of amylase leaked from the pancreas by multiplying dAmy-C by the daily drainage volume. In this study, we investigated the clinical utility of the amount of drain amylase (A-dAmy: concentration × volume) for predicting pancreatic fistula. And, we investigated the clinical utility of the combination of dAmy-C and A-dAmy for predicting pancreatic fistula. Methods We investigated patients who underwent gastrectomy for gastric cancer at Yodogawa Christian Hospital between 2012 and 2020. The optimal cut-off levels of dAmy-C and A-dAmy on postoperative day 1 for predicting Clavien-Dindo grade II or higher pancreatic fistula were calculated using receiver operating characteristic (ROC) curves. And, we calculate the positive predictive value and negative predictive value for predicting pancreatic fistula using these cut-off levels. Results A total of 448 patients were eligible for analysis. Twenty-two patients experienced Clavien-Dindo grade II or higher pancreatic fistula. ROC curves identified 1,615 IU/L as the optimal cut-off level of dAmy-C predicting pancreatic fistula. When the simple cut-off level of dAmy-C was 1,600 IU/L, the positive predictive value for was 22.8% and the negative predictive value was 99.7%. ROC curves identified 177.52 IU as the optimal cut-off level of A-dAmy predicting pancreatic fistula. When the simple cut-off level of A-dAmy was 177 IU, the positive predictive value was 21.2% and the negative predictive value was 99.7%. Using these two cut-off levels together, the positive predictive value was 34.4% and the negative predictive value was 99.7%. Conclusion A-dAmy could predict and exclude pancreatic fistula after gastrectomy as with dAmy-C. The combination of dAmy-C and A-dAmy predict pancreatic fistula more accurately than dAmy-C alone.